| Chemical Properties | white to off-white powder |
| Uses | Calpeptin is used to to inhibit the activities of cathepsin L and calpain-1. Calpeptin blocked the expression of aspartyl protease cathepsin D, amyloid precursor protein, and calparin. It acts as an inhibitor of the Ca2+-dependent protease, calpain. Prevents collagen- and thrombin-induced platelet aggregation, probably by blocking calpain induced phospholipase C and thromboxane synthase activation. Potent cathepsin L inhibitor. It is shown to preferentially inhibit a subset of protein-tyrosine phosphatases. |
| Definition | ChEBI: Calpeptin is an amino acid amide. |
| General Description | Calpeptin (Z-Leu-nLeu-H) is a cell permeable, peptide aldehyde inhibitor. It is more sensitive to calpain I compared to other inhibitors, such as Z-Leu-Met-H and leupeptin. Calpeptin stimulates neurite elongation in differentiating pheochromocytoma (PC12) cells. Calpeptin decreases microgliosis, astrogliosis, axonal damage and neuron and oligodendrocyte death in experimental autoimmune encephalomyelitis (EAE) spinal cord. Therefore, it can be considered as a potent therapeutic for treating EAE and multiple sclerosis (MS). |
| Biological Activity | Potent, cell-permeable inhibitor of the Ca 2+ -dependent protease, calpain. Prevents collagen- and thrombin-induced platelet aggregation, probably by blocking calpain induced phospholipase C and thromboxane synthase activation. Potent cathepsin L inhibitor. Recently shown to preferentially inhibit a subset of protein-tyrosine phosphatases. |
| Biochem/physiol Actions | Calpeptin is a rho kinase activator and an inhibitor of calpains, a family of calcium-dependent cysteine proteases involved in apoptosis, long-term potentiation in neurons, and cell cycle progression. |
| in vitro | calpeptin reduced production of tgf-b1, il-6, angiopoietin-1 and collagen synthesis from lung fibroblasts. calpeptin also reduced both angiopoietin-1-dependent migration and il-6-dependent proliferation of the cells, which could be the underlying mechanism of the preventive effect of calpeptin on pulmonary fibrosis [1]. |
| in vivo | the preventive effect of calpeptin has been examined on bleomycin-induced pulmonary fibrosis in mice. histological examinations and quantitative measurements of related proteins in bleomycin-treated mouse lung tissues with or without calpeptin were performed. calpeptin histologically ameliorated bleomycininduced pulmonary fibrosis in mice. results showed that calpeptin decreased the expression of il-6, tgf-b1, angiopoietin-1 and collagen type ia1 mrna in mouse lung tissues [1]. |
| IC 50 | 5 nm for human calpain 1 |
| storage | Desiccate at +4°C |
| references | [1] tabata c,tabata r,nakano t. the calpain inhibitor calpeptin prevents bleomycin-induced pulmonary fibrosis in mice. clin exp immunol.2010 dec;162(3):560-7. |
